Azo dyes and their use in color



Patented July 7, 1953 UNITED sures; ATENT" F Pics;-

AZOlDYE'SAND THEIR USELIN COLOR PHGTOGRAP-H Y Bel'aflGa'spalr," BeverlyHills, and Paul Daniel Drey-" fuss; :Vair' Nuy's, Califi, assignora bymesne assignments,to'said'Gaspar N o DrawingwtApplication November 5,1948,1

Serial-No. 58,619 a 9 Claims. (01. 95 6) fI'li'e present inventionrelates to new; 'azo dyes; to.a method for 'the'i r"preparation and-totheir usesini color photography;

Processes of color "photographyj depending L upon theidecolori'zatidn ofdyes 'in'Lthe presence A process.

of metallic silver are well. known.

of this'type inwhich azodysare employed multilayer coatingsato producecolored images, by bleaching the dyes in the presence of silver.imagesis disc'losedfina nu'mbe'rof patents,.e..g.,-

UfS. Patent 2,020,775. In lthis process. azo dyes are unifo'r'mly'rdistributed. in. photographic. rcolloids', andth'ese aIGYCOatBdJ-OIL atransparent or. opaque" support. The material. is exposed. and. 1

developed and is .then' subjected V to the. action of a bathwhichdestroysthewdye:locallyin the presence of thewme'tallici deposit.of-' the photos graphic. image results" in lthe production of'a dyeimagefwhichuis Lreversed with respect I to the metari'ma eb v In. thecO-pendin'g. patent application, Serial Nufnben537,967-," fild May. 29,1944; now Patent 1 No." 2,470,'769,Ithe're' aredescribewa number ofwherein Ar and Ar" "stand a for aliphatic' aror matic or. heterocyclic"radicals; iB .stands .foii: a

heteronuclear; bdnd linking ..'a plurality 0f dye 1. units? n stands fortheinteg'er greater than one, arid a Stand; iforan..-intege'r frdmeonentolfour c.

and the" product of d and'rh is greater ..thanstwo= r. The term.'fheteronuclearl'bond? means a link-.5"

agegfan" iatom 'ona radical l-whichqlinksla p111- rality 'ioffd'yeunit'sfziztArhdwNi iJ'Ar': provided th'atiit interrupts theconjugationmof thelcha'inh. 'Ili'e'dye. unit can be" a monoazo .dye,(a=l), a

true Vdis'az'o" Kai-2); trisazo. (a=3) For, generally, polyazo? (a -1) idye.

v Whereas in a true .polyazor dye, :the azo groups are. linked together/by -a I conjugated -'system.-and, therefore, infiuencecthew chemical andopticaliqualitie'sof eachaotherl the.

dye'unitsin the high-,inolecular weight dyes; as herein'ndefined; are,linked together I. by hetero nuclearl'bondsz Tand therefore; do notappreciably influence .the' chemical and optical qualities: of

each 'othe r; a V k abo've general formula .is validlforatha simplestcase of highmolecular: weight dyes I con-- taining.lieteronuclearbonds-, i. e. it is =valid ctorthe case:ofl-ronlyo,-biva1ent..-.heteronuclear .7 bonds ever, all or part of theheteronuclear bonds are at least trivalent; such as 1N2; the"'cyanuricif' nucleus, the pentaerythritylflresidue, etc, their.

polymeric; dyes arenot straight chains as it would appearnfrom the aboveformula; but form"- "a two-or-three dimensional. net "of .dye Dyes ofthis type, are called fcross-linked"in.

the following:

One method of obtaining dysfhavingja straight chain formed" by ,dyeunitsand hetero nuclear bonds," and of ianalogous cross-linked polymeric dyesconsists of coupling polyfunctlon'al diazocomponentswith'Zpolyfunctiona1 azo cou pling components.

} In ourecoepending application entitled Acylated" f Derivatives of 1Aminosulfonic Acids and Method for Their Preparation. Serial No.-581620ffl1d' on an .evensdate herewith, We have disclosed la number of.v"polyfunctional 'azo-c coupling com-;

ponents. Theseinew azo'coupling components,

if applied to the technique. disclosed inLappli-L cation Serial .Number537,967, are convertedfihto dyes which prove to'be of particular value.

The components ofour co-pendingrapplication' entitled AcylatedDerivatives of Amino'sulfonic Acids and a Method for TheirPreparationwhich serveas starting materialsin. the manufacture of i thenew. dyes of this invention, adhere to the general formula g,sogcation-M] 1 where R stands" for -theresidue of rnaphthalene;

whereas m 'stands' for onen-or: itw0';-' Z stands Bier- 1 0 hydrogen-ora hydrocarbon: such as": ethyl 012a pheny1-- radicals= vB(OI-.T. b:r--"St&nd$* forathesm valent residue-of a b-basic: organic acid 1 B (OHM;=3 wherein a: is greater than ionea and-.-b is atileast equal to a, suchas --CC0-,-A -v(CO-) b,

residue -=of thercyanuric'ktype f-=where: -.A stands for a fb-valentradicalp:whereb standsnforaarr integer agreaterrthan one :andvwherep-Pq= b;

hydrocarbons H Suitable coupling components from which the dyes of thisinvention may be obtained are e. g. the following:N,N-oxalyl-bis-J-acid; N,N- adipyl-bis-(N-ethyl-gamma-acid)N,N-azelaylbis-M-a-cid; N,N'-sebacyl-bis-J-acid; N,N-terephthaloyl bis Hacid; N,N m phenylenediacetyl-bis-K-acid; N,N'-diglycolyl-bis-H-acid;N,N hydroquinone O.- O diacetyl bis H acid; carbonyl bis [(4aminobenzoyl) H acid]; succinyl bis [6 (p aminophenylureido) 1 naphthol3 sulfonic acid]; N,N naphthalene 1.5 disulfo K acid; N,N'benzidinesulfonedisulfo S acid; furfurane 2,5 dicarboxylyl H acid; N,N'(benzoyl m sulfo) bis J acid;2 (p-sulfanilino) 4, 6 di[1 hydroxy 3,6disulfonaphthylamino (8)] s triazine; N,N',N"- tricarballylyl tris-J-acid; Striazine-2,4,6-tricarboxylyl-acid; adipyl bis(aminoterephthaloyl bis K acid).

The coupling compounds of the above exemplified class are coupled withpolydiazo compounds derived from polyamino compounds such as; 3,3'-diamino 4,4-dimethoxydiphenylmethane';, 1,1

di (p aminophenyl) cyclohexane; 4,4 di

(p aminobenzoyl) amino stilbene 2,2 disulfonic' acid; hydroquinone di (3amino 4 propyloxybenzyl) ether; 4,4 diaminodiphenylether; 4,4diaminodiphenylsulfone X,X disulfonic acid; sebacylbis (3 -amino 4methoxybenzylamide); adipyl bis (2 methoxy 5 amino anilide) pyrogalloltri (3 amino 4 methoxbenz yl) ether; 2,4,6 .-tri (p amino m sulfanilinos triazine and the tetrazo compounds of U. S. Patent No.'2,263, 994,such as, for example, tetrazotized sebacic-di-(4ramino-l-Nrethyl-anilide) and tetrazotized oxalic-di (4-amino-2-N-benzyltoluidide.

Among the polymeric azo dyes produced by coupling these polydiazocompounds with the above. exemplified polyfunctionalacylaminonaphtholsulfonic acids many red, magenta, violet, blue and cyandyes are found which satisfy the highest requirements for multilayerphotographic materials.

The components are easily available. 7 The dyes, having a sufficiently.high molecular weight, do not diffuse within photographic colloids; theyhave high tinctorial power, and many dyes of this class are easilysoluble, fast to light, very brilliant and are easily bleached at theplaces where metallic silver is present. They are reduced in thisbleaching process to form low molecular weight compounds which areeasily removed from the photographic colloid by washing.

Polymeric'dye's, containing polyfunctional ac-' ylaminonaphthol'sulfonic acids as coupling components can be obtained by theabove'indicated method (1. e. by coupling the polyfunctional ac:ylaminonaphtholsulfonic' acids with polydiazo compounds) or by othermethods, as will be seen from the examples below.

If the'dyes are prepared by coupling polyvalent diazo compounds withpolyfunctional acylaminonaphtholsulfoni-c acids, they will consist of alarge but undetermined number of dye units. In some cases it isexperimentally impossible to couple all available diazo functions withall available coupling positions. However, even in the case of completecoupling, a mixture of polymerhomologous dyes is formed, i. e. a mixtureof dyes which differ from each other by the number of dye units whichare present in each individual dye molecule. All dyes represented inthis mixture have the same shade but they are different in otherrespects. For example, they are adsorbed with different ease tovegetable fiber or to activated aluminum oxide, or they precipitate withdifferent case from aqueous solution by the addition of electrolytes. Itis therefore possible to separate the larger dye molecules from thesmaller ones by fractional precipitation, by fractional adsorption, bydialysis through suitable .membranes and by other means peculiar to eachcase.

It has also been found that mixtures of polymeric polydiaz'o compoundscan be .couplled with poly valent acylaminonaphthol sulfonic aci l sothat essentially each diazo group and essentially eachnaphtholresiduetakepart in thereaction (coue plingl :1), or one of thecomponents may befpresent in excess. If one of the componentsjis in}excess, the. average molecular weightfofthe poly: meric dye decreases, andthe dye willcontain terminal groupssuchas free coupling'pos'itions ordiazo groupsor derivativesoof conversion from the diazo groups whichhave marked'infiuence on. the physical properties of the dye. E. g'.,the'be-Q haviour of the dye ,in the fractionation;the vis cosity ofitsaqueous solution, its affinity to su b strata, and,itsj diffusionphotographic colloidsj vary according to the proportion of .thecomponents used in the coupling of the. dye.

The character ofthe terminal groups has furthermore some influence onthe substantivityof j the dye with respect to gelatin;v Both thesubstantivity and the molecular si'zeof the. dye contribute to its fastnesswith regard'tov diffusionl' As a small molecule, obviously comprisesmoreterminal groups than a la1 ge molecule does, we f found it advantageousin some cases to sacrifice molecular size in favor of'terminal'groups.That is, the optimum. results .with-regard'ijtodiffusion are notnecessarily obtained with dyes which are. ,7

p r o ydiez om qu'fld a Po valent coupling componentsin a ratio 1:1 but;

other coupling proportions such as2 1 or 1:2 may be preferable.Sometimes wide variations are possible, particularly when the"components con-f tainith'reei or more functional groups. For ex-.ample, to mention an extreme case, N-(3-aminog- 4 5 methoxy benzyl)anhydroaminoben'zylalcoho] canbe completely diazotized and coupled invproportions varyingbetween 4:1 and] :4 with the. product obtained froman ethylene-maleic an f hydride interpolymer and Heacid .(ourOil-pending application entitled Acylated Derivatives of i AminosulfonicAcids" and Method for Their Preparation) u from these two components donot diffuse, and all of them are easily water soluble.

Like the dyes obtained by coupling polydiazo with polyvalent couplingcompounds, other dyes I obtained by polycondensation' must not nec'esfsarily be produced with the highest molecular weight possible. Forexample, a compound comprising one diazotiz able' amino group and onecoupling function such as the intermediate of Example 2 below, if'diaz'otizedand coupled with itself, 'is converted in to a polymerhomologous All the magn'eta dyes obtainedl dyeymlxture,.particularlymhenthe .diazotization and/or. the; coupling :areincomplete. This mixa. turaofdyescan-ibeseparated intoiractinns which;are; optically identical but. are. difierentsan .-.other respects: 7 VPolymer homologous:-dye;.-mixtures:obtained byw condensing'simpleadyesshaving a plurality ofereactive terminal: greupswsuch. :as 1 aminogroups, with 'polyvalentlea-gents.such :aszhalidesof poly-.- acids, canbe likewise improved by fractionation If :a polyfunctional diazocomponent. is coupled with a .polyfunctionalcoupling component.-in..aproportion otherthani- 1:1, the :coupling product can--be modified bysubsequent additionaof .a component; ableto reactwith the terminalgroups. of said .couplingiproduct; e. g., .a dye obtained. by..coupling. a polydiazo compound with -an excess of. apolyfunctionalicoupling component, can.be modified byafter-treatmentwith a mono'diazo" compound. It must be determinedempirically in each case, inwha't proportion the dime and the couplingcomponents are to 'be combined in order to produce a non-diffusingpolymeric dye; Generally, I an excessof .sdiazo'compoundup. to100% has abeneficial efiectbn'the -fastness of thedyej with regard: to diifusion;however; .in some cases'an excess-of coupling compound up to 100% acts 7in the sameway. In other cases the. optimum results are. obtained .bycoupling 1:1. A2 to 3 percentvariation in the proportions generallycauses noticeablediffer'ences in the physical properties of the dyeobtained. In certain cases a dye, obtainedby coupling 1:1, if dissolvedandaddedt'o the emulsion, increases the visccsity'of the emulsio'n'andmakes it difiicult to obtain an even coating.- A deviation of a fewpercent from the pro'-' portion 1:1 will lowerthe-viscosity of the dyesolution withoutapprecia'bly changing thelfaste 1 ness .of :theL-dye:with regardto diffusion: 1

Example 1 1.3 mols of AA.ediaminodiphenylether is tetrazotize'd andcoupled. in aqueous pyridine with 1.0 mol of N,N"-adipyl-bis-. 1-amino-8-hydroxynaphthalene-S, fi-disulfonic acid), described in ourcopending application entitled AcylatedDerivatives of AminosulfonicAcids and Method for Their Preparation. A brilliant magneta dye'-"formswhich; if testedin photographicigelatin;shows traces ohdifiusion'w The'-dye is isolated an'd" treatedi in weakly acidicsolution-with suchanamount of alumina as to adsorb 15% of the totaldye weight. The dye insolution (85%) is completely freed fromv aluminum ions and isolated asthe sodium salt. The absorbe'd"dye*=(l5%) is eluted with sodiumcarbonate and isolated in the same manner. While the fraction which hadbe'erradso'rbed difiu'ses'about ten times as much asid-oesithe'raw'dyeythtother 85% or thedye is completely gfast .to idiffusion,- even'after prolonged treatment: in alkaline processing ;baths'. The -2-dilfusing and the non-diifusing fractions have the same absorptionspectrum; both are very Water soluble, cause no densitization of theemulsion and are quite stable to light.

If the components of the above example are coupled in a ratio 1.5:1, araw dye is obtained which diffuses less than the raw dyev obtained.

in the coup1ing'1.3:1.. This improved raw dye.- can befiractionatedinthe indicated'manner to. yield .over'90%'of a dyepwhich'iscompletelyfast i to'diffusion.

Whereas the above dyeis produced b'ycoupling. a polydiazo compound withapolyfunctionalcoue...

6 pllng-componenuzdyesof this .inventloncambetobe c tained in otherWZLYS flSEWGH-LL. p

Example 2 If this-- compound is treated with'nitrousacid atOther-s'icolors:cambeeproduced by coupli-ng the'tetrazotizeda:zdiaminodisazo :dye of= this 'Iexample with frdifier'ent.vterminal vi coupling. =-components e. 5g nonediffu'singr. red dyes are:produced:by coupling it ..with Lsuc'cinyl-Lbis: (-p aminophenyl) Ipyrazolonecarbonic l acidi or i-with glycerinei a bis-acetoaceta-te; :v

Example 4- I One-.molmf 4-chloro-2-aminoanisole is -diazotizedaandcoupled with 1 mol- 0f -N,N1(amino-. hydroquinoneu 0-a-diacetyll-i bis I-I acid- (obtained by reduetionoi-the correspondingnierr troA com-pound)-.-. The. dye.- which -forms-is isupposed to-be-wessentially= :a mono. ame-dye. This dye is .diazotized-and coupledwith: itself. whereby 5:.-

a nonedifiusinga polymeric :azo dye of undetermined moleculanweight. isformed-,

I-f .inlthefirst operation. 2. mole of chloramsidinez were. used aanaminodisaz o dye forms: :Wh'iC'hTrbYu.)

diazotization and w coupling 4 it :with 2,4-.dich-loro:-'ebenzoyleKeacid is converted into a non-difiusingsgmagneta trisazo dye.

Example 2-naphthylainine=4,8-disuli0nic acid is diazo tizednandr coupledwith l-naphthylamine-l-sulfonic acid. A monoazo dye-forms which is diazof tized and coupled-with-2 ethoxyel naphthylamine-'i-sulfonic I acid.The -disazo dye which formsaisia well known-intermediate. Itdszcusltomary in-'the'manufacture of trisazo dyes t0diazotize..tl1iss.intermediate and=couple-it With'ia.

terminal. componentawithoutparticular: precau-H tionsssHowever;inlordeinto prepare thepolyazo--- dyes =of .-this-zexample, -.it ismecessary. to isola-te saidintermediatei-n a pures-tate.- '.-It isrepeatedly dissolved: and reprecipitated: by addition. 10f salt untilall impuritiescarezremoved This puriflcaw.

tion is performed in a neutral solution, and heating of the dye shouldbe avoided.

Two molecular parts. of the disazo dye are diazotized and coupled at -lC. in 70% aqueous pyridine with one molecular part Of N,N'- adipyl bis(2 amino 5 naphthol 7 sulfonic acid). A cyan dye forms which is purifiedby reprecipitation from water and finally by precipitation with acetonefrom the aqueous solution. The dye does not difiuse and has excellentphotographic properties.

Example 6 An emulsion sensitized to red light and containing a cyan dyeis coated on an opaque support as described in Example 4 of ourco-pending application, S. N. 18,714. A silver halide gelatin emulsionsensitized to green light and containing the non-diffusing fraction ofthe magenta dye of Example 1 (0.5 gr./l00 ml. emulsion) is coatedthereon. A yellow filter layer and a blue sensitive silver halideemulsion layer containing a yellow azo dye are coated on top, tocomplete a color photographic printing material. This material isexposed to light through a colored transparency, developed, bleached ina bleaching bath such as described in U. S. Patent Re. 22,308, washed toremove the reduction products from the material, and liberated fromsilver and silver salts in known manner. A print in natural colorsresults.

Example 7 An acid suspension of one mol of tetrazotized' benzidine2,2-di sulfonic acid is poured into anv acid solution of 2.2 mols ofo-anisidine, the solution is buffered with sodium acetate until onlyweakly acidic to Congo paper, the solution is stirred for 24 hours toallow for complete coupling, heated to 80 C. and cooled. The dye isfiltered, slurried in diluted hydrochloric acid, filtered, washed withalcohol and dried.

400, grams of the dry dye are stirred into 1.6 liters Of fuming sulfuricacid S03) at a temperature below 10 C. The sulfonation mixture is keptat room temperature for three days and stirred slowly into crushed ice.The sulfonated dye is precipitated with sodium chloride, filtered andpurified by reprecipitation with sodium chloride from aqueous solution.

'A tetrazo solution, prepared from 1.1 mol of the sulfonated dye, isadded to a pyridine solution of 1.0 mol of adipyl-bis-H-acid at 0 C.After two hours the solution is heated to 70 C., cooled to roomtemperature and acidified by addition of hydrochloric acid. The dye isprecipitated by addition of salt, filtered, washed with salt solution,dissolved in water, precipitated with sodium acetate, filtered andwashed with alcohol.

The magenta dye, thus obtained, is believed to have essentially thefollowing structure:

OCH:

I S O 3N3 O 3N8, N80 38 S O 3N8.

If this dye is dissolved in a sodium carbonate solution and precipitatedwith a quantity of so-- or paper. They can be used to dye thephotographic colloid itself, or to dye up resins which afterwards may bedispersed in photographic colloids. They can be mixed with unsensitized.

emulsions or with emulsions which are sensitized to any color. They maybe incorporated in any or all desired layers of a multilayer coating.The sensitive compositions containing these dyes may be coated ontransparent or opaque supports, in single-layer or multi-layer coatings,or in multi-layer coatings on one or both sides of a support. The dyesof this invention, incorporated into one or more layers of photographicmaterial, may be bleached locally at the places where metallic silver ispresent by treatment in an acid, neutral or alkaline bleaching bath; orthey may be bleached or converted into other colored substances locallyat the places where developable silver salts are present, by treatmentin suitable developers.

The properties of the dyes of this invention,

particularly their reduced tendency to penetrate colloids, make themvaluable not only for photographic purposes; but as well in otherfields, e. g., in the dyeing of textiles and of artificial resins.

Since from the foregoingdescription of the invention it will be apparentto those skilled in the art that many variations of this invention maybe made without departing from the spirit and scope thereof, it is to beunderstood that We do not limit ourselves to the specific examplesthereof, except as defined in the appended claims.

We claim:

1. Aphotographic material including a silver containing image forming,layer and a colloid comprising an azo dye comprising at least oneradical of the formula selected from the group. consisting of hydrogen,

alkyl and aryl radicals, R. is a naphthalene nucleus, m is an integerselected from the group consisting of one and two, Y stands for abivalent aromatic radical, where the azo groups shown in the formula arepart of a total of n azo groups, said 11. groups being arranged in n dyeunits sep-' l; arated-from each otherby heteronuclear-'bonds, 1 'e'aphunit comprising v V V n n, I I

o azo groups where a stands for an integer from one to four, wheren=a.nand is greater-than b and where n f is {an integer greater than "one.

2: Aphotographic-material'including a'silvercontainingimageiori'ninglayer and a'colloid comprising an azo dyecomprising at least one radical wherein B stands for the b valentresidue of a 1)- basic organic acid B(OH) b wherein Z) is an integergreater than one, Z stands for a radical selected from the groupconsisting of hydrogen, alkyl and aryl radicals, R is a naphthalenenucleus, m is an integer selected from the group consisting of one andtwo, where the azo groups shown in the formula are part of a total of nazo groups, said n azo groups being arranged in n dye units separatedfrom each other by heteronuclear bonds, each unit comprising a azogroups where a stands for an integer from one to four, where n'=a.n andis greater than b and where n is an integer greater than one.

3. A photographic material including a silver containing image forminglayer and a colloid comprising an azo dye comprising at least oneradical (S Oication).

where Y is a bivalent aromatic radical, and m and m are each selectedfrom the group consisting of one and two said azo dye comprising atleast three azo groups.

5. A photographic material including a silver containing image forminglayer and a colloid comprising an azo dye formed by couplingtetrazotized diaminodiphenyl ether with adipyl-bis-H- acid.

i 10 6. A'process forprodu'cing'acoloredin age in a colored photographiccolloid layer containing a si1ver,.,in1age,i said; layerbeing dyed withan azo dye comprising at least one radical of the formula 10'? wherein-Bi OH) 111$. stands fornthe x valent'iresidue 5:01 abebasicorganiclacidi BiCOI-I) a, where :1: stands for an integer greaterthan one and b is an integer at least equal to :3, Z stands for aradical selected from the group consisting of hydrogen, alkyl and arylradicals, R is a naphthalene nucleus, m is an integer selected from thegroup consisting of one and two, Ystands for a bivalent aromatic radicalwhere the azo groups shown in the formula are part of a total of n azogroups, said n groups being arranged in n dye units separated from eachother by heteronuclear bonds, each unit comprising treating said colloidlayer to locally destroy by reduction said dye in the presence of saidsilver,

image.

7. A process for producing a colored image in a colored photographiccolloid layer containing a silver image, said layer being dyed with anazo dye comprising at least one radical NH OH (J 0 ection), 2

where B stands for the residue of a dibasic organic acid B(OH)2, where mis an integer selected from the group consisting of one and two, wherethe azo group shown in the formula is part of a total of n azo groupsseparated by heteronuclear bonds, and Where n is greater than two, whichcomprises treating said colloid layer to locally destroy by reductionsaid dye in the presence of said silver image.

8. A process for producing a colored image in a colored photographiccolloid layer containing a silver image said layer being dyed with anazo dye formed by coupling tetrazotized diaminodiphenyl ether withadipyl-bis-H-acid which comprises treating said colloid layer to locallyde- 60 stroy by reduction said dye in the presence of said silver image.

9. A photographic material including a silver containing image forminglayer and a colloid comprising an azo dye formed by coupling a polydiazocompound with a coupling component of the formula (S C mden)" 1 whereinR is a naphthalene nucleus, Z is a radi- Name I Date Gaspar Oct.31,-1944 Schneider et a1 May 22, 1945 Wilson Mar. 8, 1949 Gaspar ,..L May24, 1949 FOREIGN PATENTS 7 Country Date Great Britain Apr. 11, 1939Great Britain Sept. 6, 1948 Great Britain Feb. 1, 1949

1. A PHOTOGRAPHIC MATERIAL INCLUDING A SILVER CONTAINING IMAGE FORMINGLAYER AND A COLLOID COMPRISING AN AZO DYE COMPRISING AT LEAST ONERADICAL OF THE FORMULA